Failure after long uptimes
Could be a network issue, it used to be that a single program may block/clog the network if it does not read messages. This has been fixed, but some problems are still there. Sometimes restarting the network protocol translator on the Raspberry Pi solves the problem, other times it does not seem to solve it.
So far, the meter program on the power meter continues to refresh data, it does not look like a total lockup.